Support is requested for organizing the Seventh Conference on Hemoglobin Switching to take place on September 8-11, 1990. It will represent a gathering of molecular biologists, cell biologists, developmental biologists, and clinical investigators who are directly involved with studies on molecular biology of globin genes and hemopoietic cell differentiation. The duration of the conference will be three days. International participation is anticipated, and support for travel and/or lodging for 15 foreign and 45 USA participants is requested.